javascript：当再次循环遍历数组时，我希望object属性重置

Question

我正在尝试创建一个对象，其中键是年数，值是金额

vm.argiterraYearlyLocalCost = {"2016":0,"2017":0,"2018":0,"2019":0} //year(key):amount(value)

我在视图中有一个输入字段，可以让我创建新的金额，每当我添加不同的addLocalCostContributor时，它会检查条件是否匹配，金额将被添加到年份。

function addLocalCostContributor(localCost, year) {
        localCost.contributors.push({});

          for(var i=0; i < localCost.contributors.length;i++ ) {
            if(angular.isDefined(localCost.contributors[i].contributor) && localCost.contributors[i].contributor.name ==='Agriterra') {
              var amount = parseInt(localCost.contributors[i].amount);
              vm.argiterraYearlyLocalCost[year] = parseInt(vm.argiterraYearlyLocalCost[year] || 0) + amount;
            }
          }
    }

vm.argiterraYearlyLocalCost = {};//ths is intiliased in the top of angular controller

问题是，无论何时添加新金额并满足条件，金额都会增加，但它会重新开始循环。例如，我添加了firstAmount，它给了我{'2016'：firstAmount}，但是当我添加newAmount并提交它再次启动循环并且它给出{'2016'：firstAmount + firstAmount + newAmount}，而我想要的只是firstAmount + newAmount。如果我可以在每次提交时重置vm.argiterraYearlyLocalCost[year]（并且函数循环以增加属性），我将得到正确的答案。 如果有人可以从不同的眼睛看到，我无法清楚地想清楚如何以及在何处重置此属性。

Answer 1

尝试在for循环运行之前重置该年份的金额。

function addLocalCostContributor(localCost, year) {
    localCost.contributors.push({});

    vm.argiterraYearlyLocalCost[year] = 0; // <= added this line

    for (var i = 0; i < localCost.contributors.length; i++) {
        if (angular.isDefined(localCost.contributors[i].contributor) 
        && localCost.contributors[i].contributor.name === 'Agriterra') {
            var amount = parseInt(localCost.contributors[i].amount);
            vm.argiterraYearlyLocalCost[year] = parseInt(vm.argiterraYearlyLocalCost[year] || 0) + amount;
        }
    }
}

vm.argiterraYearlyLocalCost = {};